A. Field of the Invention
This invention entails a novel method, apparatus, and materials for the measurement of binding between molecules which have mutual affinity. The affinity of binding displayed by certain molecules (referred to here as binding molecules) towards other specific molecules (referred to here as ligands) is used commonly as the basis of assays to measure the quantity of a particular binding molecule or ligand in a sample.
The two molecules involved in forming a binding molecule-ligand complex are also referred to as a specific binding pair. One member of a specific binding pair is referred to as a specific binding member. This invention includes methods for performing the assays using specific binding pairs of binding molecules and ligands, with Raman light scattering as the method of detecting binding. This invention also includes materials used in performing the assays and instrumentation used to perform the assays.
An assay is a test (1) to detect the presence of a substance in a sample, (2) to identify a substance in a sample, or (3) to measure the amount of a substance in a sample. In the terminology of this field, the substance that the assay is designed to detect (or identify or measure) is called an "analyte" (a glossary of some of the terms used herein is included as an appendix to this application).
Ligand binding assays are especially relevant to medical diagnostics. In modern medical practice, ligand binding assays are routinely run on patients' blood, urine, saliva, etc. in order to determine the presence or levels of antibodies, antigens, hormones, medications, poisons, toxins, illegal drugs, etc.
New, better, cheaper, and faster assays can advance the level of health care. Such assays can provide a physician with more and better information about a patient and do so consistent with reasonable cost. In addition, by making assays easier and cheaper, a higher level of health care can be extended to less developed parts of the world. Ligand binding assays are also being used to monitor groundwater contamination, toxins and pesticides in foods, industrial biological processes, and in many areas of biological research.